Griffins IMIC How do you set it up with GArageband?

Ok,
I bought this griffin I-mic and plugged it into my Powerbook. I could see I was geting some sort of signal, but I could not hear it , or bring it into Garageband! Anybody have any advice on how to fix it?

MacRumors attracts a broad audience
of both consumers and professionals interested in
the latest technologies and products. We also boast an active community focused on
purchasing decisions and technical aspects of the iPhone, iPod, iPad, and Mac platforms.